Zheng Xinglu, Zhang Xiaolan, Hu Longfei, Chen Xixi, Zhao Zhangshu, Mao Liangliang
Department of Pathology, The People's Hospital of Pingyang, Wenzhou, China.
Department of Pathology, The Third Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.
Cytojournal. 2025 Apr 1;22:39. doi: 10.25259/Cytojournal_257_2024. eCollection 2025.
Colorectal cancer (CRC) remains one of the leading causes of cancer-related mortality worldwide, and targeted therapies for CRC are urgently needed. This study aimed to investigate the mechanisms through which rhein induces apoptosis in CRC cells, focusing on its influence on the myeloid differentiation primary response gene 88 (MYD88)/toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NF-κB) signaling pathway.
Cell Counting Kit-8 assay was conducted, with three non-cytotoxic concentrations of rhein selected for further analysis. Cells were allocated into four groups: control, 10 μM rhein, 20 μM rhein, and 50 μM rhein. Migration ability was evaluated through wound healing assay, and invasive potential was assessed using Transwell invasion assay. Apoptotic rates were determined through terminal deoxynucleotidyl transferase dUTP nick-end labeling staining. The expression levels of apoptosis-related proteins and the key components of the MYD88/TLR4/NF-κB pathway were analyzed by quantitative reverse-transcription polymerase chain reaction and Western blotting after rhein treatment.
The CRC HT-29 and SW480 cells' capacity to migrate and invade was markedly reduced by rhein treatment. ( < 0.05) while markedly enhancing the apoptotic rates ( < 0.05). This finding was marked by a reduction in the expression levels of B-cell lymphoma 2 (BCL-2) protein and messenger RNA (mRNA, < 0.05), along with a notable increase in the levels of Bcl-2-associated X and cysteinyl aspartate-specific protease 3 proteins and mRNAs ( < 0.05). The expression levels of MYD88, TLR4, and NF-κB proteins and mRNAs were substantially downregulated ( < 0.05). Adding the TLR4 agonist lipopolysaccharide partially reversed the inhibitory effects of rhein on this signaling pathway, thereby restoring some cellular functional behavior.
Rhein appears to promote apoptosis in CRC cells through the MYD88/TLR4/NF-κB signaling pathway, thus inhibiting tumor initiation and progression.
结直肠癌（CRC）仍是全球癌症相关死亡的主要原因之一，因此迫切需要针对CRC的靶向治疗。本研究旨在探讨大黄酸诱导CRC细胞凋亡的机制，重点研究其对髓样分化初级反应基因88（MYD88）/Toll样受体4（TLR4）/核因子κB（NF-κB）信号通路的影响。
进行细胞计数试剂盒-8检测，选择三种无细胞毒性的大黄酸浓度进行进一步分析。将细胞分为四组：对照组、10μM大黄酸组、20μM大黄酸组和50μM大黄酸组。通过伤口愈合试验评估迁移能力，使用Transwell侵袭试验评估侵袭潜力。通过末端脱氧核苷酸转移酶dUTP缺口末端标记染色测定凋亡率。在大黄酸处理后，通过定量逆转录聚合酶链反应和蛋白质免疫印迹法分析凋亡相关蛋白和MYD88/TLR4/NF-κB通路关键成分的表达水平。
大黄酸处理显著降低了CRC HT-29和SW480细胞的迁移和侵袭能力（P<0.05），同时显著提高了凋亡率（P<0.05）。这一结果表现为B细胞淋巴瘤2（BCL-2）蛋白和信使核糖核酸（mRNA，P<0.05）表达水平降低，同时Bcl-2相关X蛋白和半胱天冬酶3蛋白及mRNA水平显著升高（P<0.05）。MYD88、TLR4和NF-κB蛋白及mRNA的表达水平均显著下调（P<0.05）。添加TLR4激动剂脂多糖可部分逆转大黄酸对该信号通路的抑制作用，从而恢复一些细胞功能行为。
大黄酸似乎通过MYD88/TLR4/NF-κB信号通路促进CRC细胞凋亡，从而抑制肿瘤的发生和发展。
